It has previously been suggested to detect the surroundings of a vehicle, for instance using an on-board RADAR or LIDAR system, and to relate the detected objects to an approximate position, provided by a positioning system such as the global positioning system (GPS) or the inertial navigation system (INS). If the vehicle is driven along the same or a similar route in the future, the objects may be detected again, and with repeated measurements of this type the position of the objects may be determined more and more accurately. Once this has been done, detection of these objects in the future may allow the location of the vehicle itself to be determined with a higher level of accuracy than can be achieved through GPS or INS alone.
Such systems are of utility both for driver-controlled vehicles (such as conventional cars) and also for automatically or semi-automatically controlled vehicles, such as assistive and industrial mobile robots. In the latter case, the system may be used to assist in the navigation or control of the vehicle.
It is an object of the present invention to seek to provide an improved vehicle location system of this type.